Sheet feeding device



.Oct. 29. '1940.

k. T. LANG 2,220,046

SHEET FEEDING DEVICE Filed April 21, 1939 5 Sheets-Sheet 1 Oct. 29,1940. K. T. LANG SHEET FEEDING DEVICE Filed A rii 21, 19:9 5Sheets-Sheet 2 Oct. 29, '1940. 1', LANG I 2,220,046

SHEET FEEDING DEVICE Filed April 21, 1939 5 Sheqts-Sheet 3 "JnueniorOct. 29, 1940. K. T. LANG 2,220,046

SHEET FEEDING DEVICE Filed April 21, 1939 5 Sheets-Sheet 4 I III i y s568 5 Jnvemor: HM WM @24 Oct? 9, 1940- r K. T. LANG 2,220,046

' SHEET FEEDING DEVICE Fil ed April 21, 19:59 7 5 Sheets-Sheet 5 desiredoperating speed.

Patented Oct. 29, 1940 UNITED. STATES SHEET FEEDING DEVICE Karl TheodorLang, Radebeul, Germany Application April 21, 1939, Serial No. 269,082

In-Germany December 10, 1938 Claims. (Cl. 271-53) I This inventionrelates to a device for insuring accurate feeding of the sheets of asheet printing machine with respect to the gauges of the feed table.

' In some of the known devices of this class the sheets caught by thegrippers of a rotary sheet feeder are moved awayfroin the pivot of therotating feeder by special guides and are withdrawn from the feed tableat a speed greater than the circumferential speed of'the sheet feeder.The sheet guides comprise for instance toggle levers which cooperate inthe rotary motion of the sheet feeder and are controlled by a stationarycam that have to be separately controlled and curves involve arestriction to certain speeds only.

Compared with the known art,- the invention overcomes the drawbacksmentioned by employing as sheet guide a sheet carrying drum or thesurface line of the cylinder, which drum rotates about a pivoteccentricallydisposed relative to the center of the path of thegrippers. The sheet carrying drum and the grippers are connected bysuitable means. as a crank guide, to provide for equal rotary motion. Inthis way, only rotary elements are provided, and it is evident that twoconcentrically rotating members admit of any It is advantageous torender adjustable the eccentricity between the center of the path of thegrippers and that of the sheet carrying drum.

The sheet carrying drum is preferably eccentrically arranged on theshaft of the supports for the grippers, and this shaft is connected withthe drum by a coupling permitting radial motion and insuring rotarymotion.

In further accordance with the invention an additional increase in speedcan be attained by providing besides the sheet guideor press-out memberconnecting with the preliminary grippers another such member preferablyconstructed like the first one, both guides or members being guidedparallel yet oppositely in their eccentricity. By

varying the relative eccentricity the speed at which sheets arewithdrawn can be regulated.

The invention is illustrated by way of example in the accompanyingdrawings, in which Figures 1, 2 and 3 are side views of the device atdifferent operating positions;

. displaced during rotation.

Fig. 4 is a longitudinal section of the shaft of the gripper carriers,and

Figs. 5 to 7 are side views of a modification, operating with severalsheet guides or press-out members, at diiferent working positions.

More particularly:

Figure 1 shows the device at the moment when the sheet is passing fromthe feed table to the preliminary grippers;

Fig. 2 shows the device when a sheet is'transl0 ferred to the feedingmeans according to the invention;

Fig. 3 shows the position after the sheet has been. transmitted to theimpression cylinder.

The sheets I are placed in known manner on the feed table 2 and passedby the preliminary grippers 3 to the feeding device according to theinvention. 4 designates the impression cylinder provided with thegrippers 5.

The device according to the invention substantially comprises two parts.One of these parts is represented by'the grippers 6 for the sheets. Thegrippersfi are arranged on the carriers 1 and rotate about a shaft 8 ina circular path "9. The shaft 8 is rotatably disposed in the machineframe In. If only the grippers 6 were provided the sheets would be movedover their entire length in a circular path.

The second part of the device according to the invention is, however, asheet carrying drum Ii eccentrically positioned on the shaft 8 of thegripper carriers 1 and having for instance the shape shown. The centerof rotation of the drum II is located at l2; and the eccentricitybetween the shafts 8 and. I2 is designated as.

To enable the drum H to cooperate in the rotary motions of the grippers6 both the grippers 6 and the drum II are connected by suitable means,as a crank guide l3, l4, the pin l3 being positioned on the carrier 1and the drum ll having a 7 slot guide H in which the pin l3 can beradially The eccentricity a: between the center 8 of the path of thegrippers and the center l2 of the drum l I is preferably adjustable.

The device operates as follows:

When the shaft 8 is driven it drives also the grippers 6 in thedirection of rotation shown in Figs. 1 to 3. In the position shown inFig. 2 the sheet I ispressed out radially by the sheet carrying drum II, so that the acceleration of the rear end of the sheet will be equalto double the eccentricity or 22:. This involves the advantage that thesheets can be fed again more rapidly to the table 2. Tests have shownthat the device operates at a very high speed. I

In the modified device shown in Figs. 5 to 7 the gripper 6 arrangedbelow the preliminary gripper moves in the direction of the arrow shownin the circular path A, 13 indicating the path of the preliminarygripper. Eccentrically to the shaft 3 the press-out member or sheetguide is arranged which is rotatable about the pivot I2 and substan=tially comprises a cylindrical surface II formed so that at itsrunning-on end it is tangent to the circular path B when the sheet isbeing transferred. The press-out member II possesses a link-guide 28 inwhich a roll 29 rotatably disposed on the gripper 6 moves. When thegripper 6 rotates in the direction of the arrow the pressout member IIis moved also by means of the roll 29 and the link 28.

Below the press-out member I! an additional conveying gripper 3| ispositioned on a shaft 30 for guiding the sheet on the circular path C,the gripper 3| rotating in a direction opposite tothat of the gripper 6.Parallel thereto, but oppositely .eccentrically, a second press outmember is formed at 32 on the superficies 33 of a cylinder. The circularpaths A, B, C are tangent to each other. The press-out member or sheetguide 33 is driven again by a link-guide 34 and a roll 35 disposed onthe gripper 3|. The circular path C is tangent also to the path ofmotion, not shown, of the grippers of the printing cylinder 5 whichrotates in a direction opposite to that of the gripper 3i. Brushes 31,38 and'39, which may be replaced of course by blasts, etc., smooth thesheet i during operation.

The device shown in Figs. 5 to 7 functions as follows:

In the position shown in Fig. 5 the preliminary gripper 3 receives thesheet I from the table 2, the gripper 6 being in a position immediatelypreceding taking over. In the position shown in Fig. 6 the sheet I istaken by the gripper 6 from the preliminary gripper 3 and withdrawnfurther, the press-out member or sheet guide II cooperating in therotary motion. Owing to its eccentric position and its form, the memberII extends during its rotation with a portion of the circumference ofthe cylindrical surface beyond the range of the circular path A, wherebyquicker withdrawal of the sheet I from the table 2 is effected. After arotation of approximately from the point of transition the sheet I isdelivered by the gripper 6 to the gripper 3i rotating in oppositedirection. During the rotation of the gripper 3| the press-out member orsheet guide 33 acts in a similar manner as the member II aaaogo ie -thesheets of a sheet printing machine with respect to the gauges of thefeed table, in which the sheets caught by rotating grippers are pressedout of the path of the grippers by special means to accelerate the rearend of the sheets, characterized in that the press-out member is a sheetcarrying drum or a portion of a cylindrical surface rotating about acenter eccentrically located relative to the center of the path of thegrippers, and that the grippers and the sheet carrying drum areconnected by suitable means, as a crank guide, to insure uniform rotarymotion, said guide being in the head members of the press out drum.

2. A device according to claim 1, in which the degree of eccentricitybetween the center of the path of the grippers and that of the sheetcarrying drum is adjustable.

3. A device according to claim 1, in which the sheet carrying drum iseccentrically arranged on the shaft of the gripper carriers and saidshaft is connected with said drum by'a coupling permit tingradial motionand enforcing rotary motion.

4. A device according to claim 1, in which the press-out memberconnecting with the preliminary, gripper connects with a second sheetpressout member.

5. A device according to claim 1, in which the press-out memberconnecting with the preliminary gripper connects with a second sheetpressout member which is of the same or similar type as the firstpress-out member.

6. A device according to claim 1, in which the press-out memberconnecting with the preliminary gripper connects with a second sheetpressout member of the same or similar type as the first press-outmember and the said two members, with respect to eccentricity, arepreferably directed parallel but oppositely so.

7. A device according to claim 1, in which the running-on surface of thepress-out member having the form of the superficies of a cylinder istangent to the path of the front edge of the sheet determined by theconveying grippers.

8. A device according to claim 1, in which the press-out memberconnecting with the preliminary gripper connects with a second sheetpressout member of the same or similar type as the r air means, areassociated with the press-out members. I

9. A device according to claim 1, .in which a plurality of press-outmembers are arranged one after the other, the number and dimensionsthereof depending upon the length of the sheets.

10. A device according to claim 1-, in which a plurality of press-outmembers are arranged one after the other, the number and v dimensionsthereof depending upon the length of the sheets, and the eccentricitiesof said members are variable relative to one another.

KARL THEODOR LANG.

